Age of father is seven times the age of his son. In the next 10 years, the age of father will be three times the age of his son. What is the age of father now?

35 Yr

Let the age of son be x, so according to question, father's age be 7x.

After 10 years:

7x + 10 = 3(x + 10)

7x + 10 = 3x + 30

4x = 20

x = 5 i.e. age of son is 5

Present age of father is 7x = 7(5) = 35 years